THE DESIGN OF THE E PROGRAMMING LANGUAGE

E is an extension of C++ designed for writing software systems to supp ort persistent applications. Originally designed as a language for imp lementing database systems, E has evolved into a general persistent pr ogramming language. E was the first C++ extension to support transpare nt persistence, the first C++ implementation to support generic classe s, and remains the only C++ extension to provide general-purpose itera tors. In addition to its contributions to the C++ programming domain, work on E has made several contributions to the field of persistent la nguages in general, including several distinct implementations of pers istence. This paper describes the main features of E and shows through examples how E addresses many of the problems that arise in building persistent systems.